Burned shale and method of preparing the sake



comma Mm UlUbb HUIUIUIIUU Examin OSCAR OLSEN, OF OAKLAND, CALIFORNIA.

BURN ED SHALE AND METHOD OF PREPARING THE SAME, AND CONCRETE MADE THIEBEFROH.

li'o Drawing.

To all whom it may concern Be it known that I, OSCAR OLSEN, a citizen of the United States, and a. resident of Oakland, county of Alameda, and State of 6 Califorma, have invented a new and useful Burned Shale and Method of Preparing the Same, and Concrete Made Therefrom, of which the following is a, specification.

My invention relates to a new material 10 having a very large variet of uses. In its chief use it may be classi ed as a building and construction material. Another importanlt use is as a refining or purifying mat/er1a An object of the invention is to provide a relatively light chemically inert, porous material useful in the refining of sugar or 01 Another object of the invention is to provide a light, inert material highly resistant to stresses to take the place of the usual sand and crushed rock in concrete.

Another object of the invention is to rovide a concrete havin a high elastic imit or coefficient of elasticity, and a high ultimate compressive strength.

The invention possesses other features of advantage, some of which, with the foregoing, will be set forth in the following de- 80 scription of the preferred form of my ing vention. It is to be understood that I may adopt variations of the preferred form with- Y in the scope of my invention as set forth in the claims.

In the practice of my invention I take x shale rock which has preferably been decomposed by'the action 0 the elements and burn jc it in a. kiln or otherwise subject it to a 55mperature of 2000 de rees Fahrenheit or above 40 for a perimmflature of the h rock, so that all organic matter therein is destroyed and it is reduce 2 porous,

X j" W Sha' es vary w1e y in tIIGlI ,l c emical composition, usually containing in l I, varying proportions dioxids of silicon and \J carbon, and oxids of aluminum, manganese and calcium,together with other substances in small and varying amounts. I do not know the exact composition a of the shale after it has been burned, but have found that it is inert ohemicall in the presence of air, water, sea water an many other substances, and that it is a dead material, that is, there Specification of Letters Patent.

Application filed lay 22, 1918. Serial No. 235,988.

Patented Sept. 2, 1919.

are no latent possibilities of chemical reaction within the substance itself.

After burniiilgdthe dshale, the Tresultant pieces are crus e an raded. he ver fine materimsuperio r'refi'nin agent ii the refining of sugar and oil, an for this purplose displaces the commonly used fullers eart The larger pieces of the material I substitute for crushed rock in the preparatlon of concrete, the finer particles being substituted for sand in the mixture.

The proportions of coarse and fine material in the concrete mixture of my invention will vary according to the nature of the work, but for ordinary construction, the following proportions 've satisfactory results.

4 parts of burner? shale oarsel crushed in place of the usual rockfifl'paiis burned shale finel crushed in lace of the usual sand, part 0 -Portlan cement and sulficient water which has Been preferably boiled and 000 e and is free from salt or alkali. By the addition of 10% ma esia cement to the Portland cement in the above mixture a concrete is produced which has a hard smooth surface capable of taking a polish. It is therefore suitable for floors or imitation marble work, or for other ornamental uses. The magnesia cement also adds to the strength of the concrete. The above proportions may be altered, or other ingredients may be added, such as Keens cement, pl gg'qoiggils, or lime, to produce a superlor har wal plaster or mortar for tiling, or for casting or ornamental work.

Concrete made according to the 421 formula first above given and preferably with magnesia cement forming 10% of the cement content will weigh from 80 to 84 pounds per cubic foot, It will resist a temperature of 3,800 degrees F. without injury and is therefore absolutely fireproof. It is a non-conductor of electricity and of heat, and excellent sound-proofing material and is unaffected by the elements, or salt water. One of the most valuable of its properties is its high elastic limit, which especially adapts it for use in ship construction. Its light weight and its great tensile and compressive strength are additional qualities which adapt it for such use. Compared with ordinary concrete made of sand and rock, my concrete requires less than half the amount of,reinforcement, and has about four times the compressive strength.

If a spike or nail is driven into a wall formed of my concrete within several weeks after erection, the nail or spike will bed firmly therein as though in wood. ,Because of its elastic qualities, great strength and light weight, it is, among many other uses, particularly suitable for telephone poles, posts. piles for all purposes and especially marine work. barges and ships, railroad ties,

bridges, buildings and mining timbers,

floors.

In the term magnesia cement I include the well known article of commerce composed largely of ma esium chlorid and ma nesium oxid, and a so cement ma e from Burned ma nesite which may be largely magnesium oxid.

I claim:

1. A composition of matter comprising a mixture of coarse and fine pieces of shale rock which have been burned but not clinkered.

Q. The method of making concrete which consists in burning without clinkering shale rock, crushing the burnt material into fine and coarse pieces, and mixing a mixture of said fine and coarse Pieces with a binding 30 material.

3. An article of manufacture comprising naturally decomposed shale rock which has been burned but not clinkered.

4. The method of preparing shale rock for use as an aggregate which consists in burning the rock, crushing it, and treating the crushed and burned material to eliminate the pulverulent particles. 4

5. Concrete comprising as an ingredient naturally decomposed shale rock which has been burned but not clinkered.

6. A concrete comprising Portland cement and an aggregate consisting entirely of finely crushed burned shale rock and coarsely crushed burned shale rock.

7. A concrete comprising burned shale rock Portland cement, and magnesia cement.

8. A concrete comprising coarsely crushed burned shale rock, finely crushed burned shale rock, Portland cement, and magnesia cement.

9. A concrete comprising ingredients in the following proportions: coarsely crushed burned shale rock 4 parts, finely crushed burned shale rock 2 parts, and 1 part of cement composed of 90% Portland cement and 10% magnesia cement.

10. The method of making concrete which consists in burning shale rock, crushing the burnt material into fine and coarse pieces, and mixing a mixture of said fine and coarse pieces with a binding material and water.

11. A concrete comprising a binding material and an ag gate consisting entirely of finely crushed burned shale rock and coarsely crushed burned shale rock.

'12. The method of making concrete which,

consists in burning shale rock and mixing the burned material with Portland cement,

ma esia cement and water.

n testimon whereof, I have hereunto set my hand at akland, California, this 17th 

